The present invention relates to a setting device for needle selecting devices, particularly for selecting apparatuses of a multisystem circular knitting machine wherein each needle selecting apparatus of a system includes at least one set of superposed selection blades movable between a rest position and a working position, and a common locking member which locks the entire set of blades in their adjusted positions in which they act on control bars of swing selectors on the needle cylinder of the knitting machine which in turn control the needles into their operating positions.
The needle selecting devices of this type provide selection of individual needles for knitting a pattern of a limited size whereby the pattern is cyclically repeated after each revolution of the machine. The pattern is fixedly set and retained in the respective needle selecting apparatuses. The device enables the production of patterns of small periodicity or limited texture combinations. The height of the pattern is limited by the number of systems of the machine and the width of the pattern is limited by the number of control butts of the selector bars. Knitted fabrics with small patterns of this kind, depending on their field of use and fashion, are in increased demand. A substantial factor affecting the demand is the provision of a circular knitting machine which is cost effective and reliable in operation and which in contrast to machines having electronically controlled pattern selectors are provided with needle selecting apparatuses which are simpler in design. Hitherto, such simple needle selecting apparatuses have been set according to a desired pattern by hand. A setting or resetting is always necessary when a fabric having a different pattern or texture is to be produced. The setting of conventional needle selecting apparatus requires long setting times leading to protracted idling of the machine. It makes no difference if the selecting apparatuses are reset directly on the machine or if the apparatuses are replaced by a new set of preset apparatuses. In both instances considerable setting times are necessary. In the case when the selecting apparatuses are exchanged the cost of the duplicated equipment and the corresponding maintenance and storage costs multiply and also a considerable installation and adjustment expenditures result.
It is known to set such needle selecting apparatuses by means of pattern cards, pattern combs or loose selecting blades. However, such pattern cards, combs and the like must be first provided with the requisite cutouts and must be installed on the selecting apparatus when needed. The setting combs have the disadvantage, apart from their susceptibility to displacement, that they become completely useless when the particular pattern is no longer needed. In addition, even if a single mistake occurs in the production of a comb, the latter is no longer applicable. Also, when using the prepared pattern determining elements the setting time for the selecting apparatuses is not substantially shorter in comparison with the installation work.
Attempts have been made to store several patterns on a drum. This method leads to expensive needle selecting apparatuses and the pattern storage is limited to a small number of patterns. In circular knitting machines having a large number of systems the application of voluminous storage drums due to the minute distance between the systems is not possible. The storage drums are usually complemented with pins or pattern combs and are also prepared manually with concomitant high preparation times.
The needle selecting apparatuses are always set or reset during the standstill of the machine or apart of the machine. This process cannot be compared with that for the needle selection devices for large area Jacquard patterns where the switchovers are carried out in running machine and the selection in the machine cycles is different.